Class EventPattern

Events in Amazon CloudWatch Events are represented as JSON objects. For more information about JSON objects, see RFC 7159.

Inheritance

System.Object

EventPattern

Implements

IEventPattern

Namespace: Amazon.CDK.AWS.Events

Assembly: Amazon.CDK.AWS.Events.dll

Syntax (csharp)

public class EventPattern : Object, IEventPattern

Syntax (vb)

Public Class EventPattern
    Inherits Object
    Implements IEventPattern

Remarks

Important: this class can only be used with a Rule class. In particular, do not use it with CfnRule class: your pattern will not be rendered correctly. In a CfnRule class, write the pattern as you normally would when directly writing CloudFormation.

Rules use event patterns to select events and route them to targets. A pattern either matches an event or it doesn't. Event patterns are represented as JSON objects with a structure that is similar to that of events.

It is important to remember the following about event pattern matching:

See: https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/CloudWatchEventsandEventPatterns.html

ExampleMetadata: infused

Examples

using Amazon.CDK.AWS.Lambda;


var fn = new Function(this, "MyFunc", new FunctionProps {
    Runtime = Runtime.NODEJS_14_X,
    Handler = "index.handler",
    Code = Code.FromInline("exports.handler = handler.toString()")
});

var rule = new Rule(this, "rule", new RuleProps {
    EventPattern = new EventPattern {
        Source = new [] { "aws.ec2" }
    }
});

var queue = new Queue(this, "Queue");

rule.AddTarget(new LambdaFunction(fn, new LambdaFunctionProps {
    DeadLetterQueue = queue,  // Optional: add a dead letter queue
    MaxEventAge = Duration.Hours(2),  // Optional: set the maxEventAge retry policy
    RetryAttempts = 2
}));

Synopsis

Constructors

EventPattern()

Properties

Account	The 12-digit number identifying an AWS account.
Detail	A JSON object, whose content is at the discretion of the service originating the event.
DetailType	Identifies, in combination with the source field, the fields and values that appear in the detail field.
Id	A unique value is generated for every event.
Region	Identifies the AWS region where the event originated.
Resources	This JSON array contains ARNs that identify resources that are involved in the event.
Source	Identifies the service that sourced the event.
Time	The event timestamp, which can be specified by the service originating the event.
Version	By default, this is set to 0 (zero) in all events.

Constructors

EventPattern()

public EventPattern()

Properties

Account

The 12-digit number identifying an AWS account.

public string[] Account { get; set; }

Property Value

System.String[]

Remarks

Default: - No filtering on account

Detail

A JSON object, whose content is at the discretion of the service originating the event.

public IDictionary<string, object> Detail { get; set; }

Property Value

System.Collections.Generic.IDictionary<System.String, System.Object>

Remarks

Default: - No filtering on detail

DetailType

Identifies, in combination with the source field, the fields and values that appear in the detail field.

public string[] DetailType { get; set; }

Property Value

System.String[]

Remarks

Represents the "detail-type" event field.

Default: - No filtering on detail type

Id

A unique value is generated for every event.

public string[] Id { get; set; }

Property Value

System.String[]

Remarks

This can be helpful in tracing events as they move through rules to targets, and are processed.

Default: - No filtering on id

Region

Identifies the AWS region where the event originated.

public string[] Region { get; set; }

Property Value

System.String[]

Remarks

Default: - No filtering on region

Resources

This JSON array contains ARNs that identify resources that are involved in the event.

public string[] Resources { get; set; }

Property Value

System.String[]

Remarks

Inclusion of these ARNs is at the discretion of the service.

For example, Amazon EC2 instance state-changes include Amazon EC2 instance ARNs, Auto Scaling events include ARNs for both instances and Auto Scaling groups, but API calls with AWS CloudTrail do not include resource ARNs.

Default: - No filtering on resource

Source

Identifies the service that sourced the event.

public string[] Source { get; set; }

Property Value

System.String[]

Remarks

All events sourced from within AWS begin with "aws." Customer-generated events can have any value here, as long as it doesn't begin with "aws." We recommend the use of Java package-name style reverse domain-name strings.

To find the correct value for source for an AWS service, see the table in AWS Service Namespaces. For example, the source value for Amazon CloudFront is aws.cloudfront.

Default: - No filtering on source

See: http://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html#genref-aws-service-namespaces

Time

The event timestamp, which can be specified by the service originating the event.

public string[] Time { get; set; }

Property Value

System.String[]

Remarks

If the event spans a time interval, the service might choose to report the start time, so this value can be noticeably before the time the event is actually received.

Default: - No filtering on time

Version

By default, this is set to 0 (zero) in all events.

public string[] Version { get; set; }

Property Value

System.String[]

Remarks

Default: - No filtering on version

Implements

IEventPattern